Display device, liquid crystal display device, electronic apparatus, and display device manufacturing method

ABSTRACT

To provide a low-cost display device which can accurately detect a position touched by a finger. A display device displays an image by having display elements capable of performing electro-optic responses formed between conductible first and second substrates, and detects a contact position touched by a contact body by having a conductive impedance surface formed on the second substrate side. The display device includes: linearization pattern sections formed on the first substrate, which include a plurality of electrodes capable of detecting electric currents on a conductive impedance surface; and a conductive member which electrically connects the linearization pattern sections with the conductive impedance surface on the second substrate.

CROSS-REFERENCE TO RELATED APPLICATION

This application is based upon and claims the benefit of priority fromJapanese patent application No. 2008-101967, filed on Apr. 9, 2008, thedisclosure of which is incorporated herein in its entirety by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a display device, a liquid crystaldisplay device, an electronic apparatus, and a display devicemanufacturing method. More specifically, the present invention relatesto a display device and the like provided with a touch sensor that iscapable of detecting positions touched by a finger or a pen.

2. Description of the Related Art

A touch sensor is a device for detecting positions touched by a fingeror a pen, and it is normally used in combination with a display devicesuch as a liquid crystal display device (LCD), a plasma display device(PDP), or the like.

The touch sensor is utilized to one of man-to-machine interfaces, suchas a keyboard, a mouse, and the like of a computer. The output signalsof the touch sensor are generated by touching directly prescribedpositions such as button images on a screen of a display device with acontact body such as a human finger or a pen to the computer and theoutput signals control an apparatus or to control display contents ofthe display device. The display with the touch sensor (hereinafterreferred to as a touch panel) are currently put into practical use inportable information terminals, ticket-vending machines, automatedteller machines (ATM), car navigation systems, copying machines, and thelike.

An analog capacitance coupling type, a resistance film type, an infraredtype, an ultrasonic type, and an electromagnetic inducing type are knownas the types of the touch sensor. Among those, the analog capacitancecoupling type is further classified into a projected capacitive type anda surface capacitive type.

The surface capacitive type touch sensor is configured with atransparent substrate, a uniform transparent conductive film formedthereon, and a thin insulating film formed thereon.

When driving the touch sensor, an AC voltage is applied from the fourcorners of the transparent conductive film. When the touch sensor istouched by a finger, a small electric current is flown in the fingerbecause of a capacitance formed between the touched surface and thefinger. The electric currents flow from each corner of the film to thetouched point.

Then, a controller obtains the ratio of the electric currents from eachcorner and calculates the coordinates of the touched position. Regardingthe technique of the surface capacitive type touch sensor, JapaneseExamined Patent Publication 56-500230 (Patent Document 1) discloses abasic concept device.

However, when the AC voltages are simply applied to the transparentconductive film from the four corners, an electric field linesdistributed on the transparent conductive film becomes curved andnon-linear. Therefore, the touched positions by a finger or a pen cannotbe detected accurately. Techniques for overcoming such issue aredisclosed in Patent Document 1 and Japanese Patent No. 3121592 (PatentDocument 2).

Those Documents mention about linearization patterns provided on theouter periphery of a transparent conductive film. An electric field isextended from the linearization pattern provided in each side of theouter periphery towards the counter side, and the electric fieldintensity becomes constant in a direction perpendicular to therespective sides of the outer periphery. That is, regarding thepotential distribution on the transparent conductive film, equipotentiallines in parallel to each side of the outer periphery are formed, andthe pitches of the equipotential lines become uniform and linear.Therefore, the relation between the potential distribution on thetransparent conductive film and the corresponding finger touchedpositions can be simplified.

Patent Document 1 discloses a structure which superimposes conductivesegments on a resistive surface (referred to a conductive impedancesurface hereinafter) by silk screening printing technique (from theseventh line to the twelfth line of lower left section of p. 5 of PatentDocument 1, and FIG. 5 of Patent Document 1).

Further, also disclosed is an example which arranges conductive segmentsin a geometric pattern, and repeatedly corrects the system of anisochrone equation showing the resistance net between the segments toobtain the optimum geometric shape (from the thirteenth line to theeighteenth line of lower left section of p. 5 of Patent Document 1, andFIG. 6 of Patent Document 1).

With the above, the degrees of the current density and the directionsthereof at any points on a plane become uniform on the conductiveimpedance surface, thereby providing a resistive surface which generateslinear electric fields.

Further, Patent Document 2 discloses an example which provideslinearization patterns along the edges of a position detectingconductive film (hereinafter referred to as a position detecting film)of a counter substrate side for making electric field lines uniform(paragraph 0017 of Patent Document 2, FIG. 5 of Patent Document 2).Further, in the example of Patent Document 2, a layer of a positiondetecting film is formed on the counter substrate, and a layer oflinearization patterns is further formed on the layer of the positiondetecting film (FIG. 7 of Patent Document 2).

In the meantime, the latest technology trends regarding the analogcapacitance coupling type are disclosed in “Technologies andDevelopments of Touch Panels” supervised by Yuji MITANI, CMC publishingCO., LTD. Dec. 1, 2004, pages. 54-64 (Non-Patent Document 1). For thetouch sensor of the analog capacitance coupling type of a relatedtechnique, a touch sensor of a surface capacitive type formed on atransparent substrate is attached on a display device to be used.

However, such structure has the touch sensor provided further on thedisplay screen, so that there are some issues to be overcome, e.g., anincrease in the thickness of the device itself, an increase in the cost,and deterioration of the display quality by putting the touch sensor onthe display. Techniques for overcoming such issues are disclosed inJapanese Unexamined Patent Publication 2003-99192 (Patent Document 3)and Japanese Unexamined Patent Publication 2003-66417 (Patent Document4).

Patent Document 3 discloses a device which calculates positioncoordinates of a touched position based on electric currents at the fourcorners by having current detectors provided the four corners on acounter electrode surface which applies voltages to a liquid crystal.

Patent Document 4 discloses a device which includes: a liquid crystaldisplay (LCD) circuit for supplying display voltages or currents to atransparent conductive film; a position detecting circuit for detectingelectric currents flown from a plurality of points of the transparentconductive film; and a switching circuit for making a counter electrodeand one of those circuits electrically conductive.

Further, Patent Document 4 discloses an example which uses the counterelectrode surface to function as a position detecting conductive film(transparent conductive film) (0030 of Patent Document 4), and positiondetecting electrodes for detecting positions of applied voltages areformed at the four corners of the position detecting conductive film.Furthermore, Patent Document 4 discloses an example which forms aplurality of position detecting electrodes along the periphery of thecounter electrode surface.

With the techniques of Patent Documents 3 and 4, the common (COM)electrode or the transparent conductive film for LCD drive circuitfunctions as the transparent conductive film of the surface capacitivetype touch sensor, so that it is unnecessary to additionally provide asurface capacitive type touch sensor to the display device. As a result,it is possible to overcome the issues such as an increase in thethickness of the device itself, an increase in the cost, anddeterioration of the display quality.

However, there are still remained issues with the display devicesdisclosed in Patent Documents 3 and 4 as follows.

That is, while Patent Documents 3 and 4 are described to utilize thecounter electrode surface as the transparent conductive film fordetecting positions in order to overcome the issues such as theincreases in the thickness of the device itself and the cost, there isno depiction about a specified structure and method for forming thelinearization patterns.

Therefore, the display devices disclosed in Patent Documents 3 and 4 aresuited for reducing the weight, the size, and the thickness, but notcapable of correctly detecting the positions touched by a finger or apen.

In the meantime, the method for forming the linearization patternsaccording to the related technique is a screen printing of a conductivepaste, etc., as depicted in Patent Document 2. For such method, it isnecessary to add a step for forming the linearization patterns, and toprovide a special manufacturing device such as a screen printing device.

Further, the conductive paste for the linearization patterns is normallymade with fine powders of noble metals such as silver, so that suchexpensive material is required.

As a result, the cost for manufacturing the display devices is increasedif the techniques of Patent Documents 3 and 4 and the technique ofPatent Document 2 are simply combined in order to form the linearizationpatterns on the counter electrode.

SUMMARY OF THE INVENTION

The present invention has been designed to overcome the issues of theabove-described techniques. It is therefore an exemplary object of theinvention to provide a display device and the like, which can detect thetouched positions correctly and can be formed in small and thin type ata low cost.

In order to achieve the foregoing exemplary object, the display deviceaccording to an exemplary aspect of the invention is a display devicewhich displays an image by a plurality of display drive elements capableof performing electro-optic responses of liquid crystal sealed between afirst and a second substrates. The display device includes:

the first substrate, on which linearization pattern sections, a controlpart of the display drive elements, and their wirings are formed;

the second substrate which has a conductive impedance surface formedthereon, measures electric current values flown between a plurality ofpoints and a touched point by a contact body and detect a contactposition; the first substrate opposing against the conductive impedancesurface on the second substrate, on which linearization patternsections, a control part of the display drive elements, and theirwirings are formed;

and an electrical conductive member which electrically connects thelinearization pattern sections and the conductive impedance surface.

The display device manufacturing method according to another exemplaryaspect of the invention is a manufacturing method of a display devicethat is capable of displaying an image by having display elements(pixels) capable of performing electro-optic responses formed betweenfirst and second substrates, including:

a first step which performs to form linearization pattern sectionsincluding a plurality of their electrodes in a peripheral area of apixel matrix part on the first substrate, simultaneously with a step forforming a plural of pixel electrodes on the first substrate or a stepfor forming wirings on the first substrate;

a second step which forms, on the second substrate, a counter electrodefunctioning as the conductive impedance surface; and

a third step which forms a conductive member between the linearizationpattern sections and the counter electrode, which are capable ofperforming linearization of electric fields of the conductive impedancesurface and capable of detecting electric currents on the conductiveimpedance surface.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view showing an example of a schematic structureof a display device according to a first exemplary embodiment of theinvention;

FIG. 2 is a plan model illustration showing an example of a schematicstructure which illustrates a relation between linearization patternsections and an anisotropic conductor of the display device according tothe first exemplary embodiment of the invention;

FIG. 3 is a fragmentary sectional view showing an I-I′ part of FIG. 2;

FIG. 4 is a plan model illustration showing an example of linearizationpattern sections which can supply uniform voltages to four sides ofouter periphery of a transparent conductive film according to the firstexemplary embodiment of the invention;

FIG. 5 is a sectional view which schematically shows an example of aschematic structure of the display device according to the firstexemplary embodiment of the invention;

FIG. 6 is a timing chart which schematically shows a state of voltagesof main electrodes of the display device according to the firstexemplary embodiment of the invention;

FIG. 7 is a plan model illustration showing an example of a schematicstructure which illustrates a relation between linearization patternsections and an anisotropic conductor of a display device according to asecond exemplary embodiment of the invention;

FIG. 8 is a plan model illustration showing an example of a schematicstructure which illustrates a relation between linearization patternsections and an anisotropic conductor of a display device according to athird exemplary embodiment of the invention;

FIG. 9 is a fragmentary sectional view showing a II-II′ part of FIG. 8;

FIG. 10 is a plan model illustration showing an example of a schematicstructure which illustrates a relation between linearization patternsections and an anisotropic conductor of a display device according to afourth exemplary embodiment of the invention;

FIG. 11 is a fragmentary sectional view showing an III-III′ part of FIG.10;

FIG. 12 is a plan model illustration showing an example of a schematicstructure of a display device according to a fifth exemplary embodimentof the invention;

FIG. 13 is a perspective view showing a potential distribution of acounter electrode of the display device shown in FIG. 12;

FIG. 14 is a plan model illustration showing an example of a schematicstructure of a display device according to a sixth exemplary embodimentof the invention;

FIG. 15 is a timing chart which schematically shows a state of voltagesof electrodes of the display device shown in FIG. 14;

FIG. 16 is a plan model illustration showing an example of a schematicstructure which illustrates a relation between linearization patternsections and an anisotropic conductor of a display device according to aseventh exemplary embodiment of the invention;

FIG. 17 is a fragmentary sectional view showing a IV-IV′ part of FIG.16;

FIG. 18 is a plan model illustration showing an example of a touch panelto which linearization pattern sections according to a related techniqueare provided; and

FIG. 19 is a fragmentary sectional view showing a V-V′ part of FIG. 18.

DETAILED DESCRIPTION OF THE EXEMPLARY EMBODIMENTS

Hereinafter, an example of exemplary embodiments of the invention willbe described in a concretive manner by referring to the accompanyingdrawings.

First Exemplary Embodiment

(Overall Structure of Display Device)

First, a specific structure of a display device according to thisexemplary embodiment will be described in order from the overallstructure to the detailed structure of each part. FIG. 1 is aperspective view showing an example of an overall schematic structure,which schematically illustrates a display device with a built-in touchsensor according to a first exemplary embodiment of the invention.

As shown in FIG. 1, a display device 1 of this exemplary embodiment is aliquid crystal display device (LCD) which includes a touch sensor thatis capable of detecting touches of a finger or a pen on a display screenand position coordinates thereof.

Other than the liquid crystal display device, the display device 1 canalso be a display device such as a plasma display device (PDP), anorganic EL display device, or the like.

The display device 1 is configured, including a display device substrate10, a counter substrate 19, and a polarizing plate (not shown).

The display device substrate 10 is a substrate on which electrodes(correspond to signal lines (signal electrodes) 4, scanning lines(scanning electrodes) 6, storage capacitance lines (storage capacitanceelectrodes) 8 of FIG. 1) for supplying electric signals to a liquidcrystal 2 as an example of display element in a display area are formed.A pixel matrix part is formed in the display area on the surface of thedisplay device substrate 10 opposing to the counter substrate 19 side.The pixel matrix part is configured with a plurality of signal lines(reference numeral 4 in FIG. 1), a plurality of scanning lines(reference numerals 6 in FIG. 1) crossing with the signal lines, storagecapacitance lines (reference numeral 8 in FIG. 1) provided between thescanning lines, and pixel circuits arranged by corresponding to eachintersection point.

The pixel circuit has a pixel switch TFT (Thin Film Transistor), astorage capacitance, and a pixel electrode. In the pixel switch TFT(switching element), the scanning line 6 for controlling on/off of theTFT is connected to a gate electrode, the signal line 4 for supplyingsignals to the pixel electrode is connected to either a drain electrodeor a source electrode of the TFT, and the storage capacitance and thepixel electrode are connected to the remainder (the drain electrode orthe source electrode). The storage capacitance is connected to thecorresponding storage capacitance line 8.

FIG. 1 schematically shows a case having two each of scanning lines 6and signal lines 4. However, the pixel circuit can be designedarbitrarily.

A scanning line driving circuit 14, a signal line driving circuit 15,and a storage capacitance line driving circuit (not shown) for drivingthe pixel matrix part are provided in the outer peripheral part of thedisplay area in the display device substrate 10. The scanning linedriving circuit 14 is a circuit for driving the scanning lines 6.

The signal line driving circuit 15 is a circuit for driving the signallines 4. The storage capacitance line driving circuit is a circuit forsupplying voltage signals to the storage capacitance line 8, and it isconnected to a COM electrode.

Note here that a “display element control part” can be configured withthe pixel circuit, the scanning line driving circuit 14, the signal linedriving circuit 15, the storage capacitance line driving circuit, andthe like. Further, the signal lines 4, the scanning lines 6, the storagecapacitance lines 8, and the like can simply be referred to as “wirings”(driving wirings). Furthermore, the driving wirings together withtouched-position detecting wirings described later can be referred to as“wirings”, or either one of the wirings can be referred to as “wirings”as well.

Linearization pattern sections 30 are provided in a peripheral area ofthe outer peripheral part of the display area of the display devicesubstrate 10.

Reference numerals of the linearization pattern sections will be definedhere. In FIG. 1, the whole pattern painted black is generally referredto as the linearization pattern sections 30. Among those, fourlinearization pattern sections provided in the vicinity of the fourcorners (corner areas) connected to wirings 32 (touched-positiondetecting wirings) which configure a wiring part are defined as 30 a(first pattern sections), and other linearization pattern sectionsprovided on the four sides of the outer periphery (side areas) aredefined as 30 b (second pattern sections).

As shown in FIG. 2, the linearization pattern sections 30 b (secondpattern sections) further include longer outer-periphery side patterns30 b-1 on the outer-periphery side and shorter inner-periphery sidepatterns 30 b-2 on the inner-periphery side.

Furthermore, the linearization pattern sections 30 a (first patternsection) are not limited to be formed in the four corners but may beformed at least two or more corners.

Each of the linearization pattern sections 30 a provided in the vicinityof the four corners of the display device substrate 10 is connected to acrimp contact (not shown) of an FPC (flexible printed circuit) 38 viathe wirings 32 connected thereto.

The crimp contact of the FPC is connected to an external substrate 20 (acontrol circuit substrate capable of loading a control circuit and thelike) via the FPC 38, and it is electrically connected to a single-poledouble-throw type switch 21 of the external substrate 20.

The switch 21 has an AC voltage source 22 electrically connected to oneof the connections thereof via a current detecting circuit 13, and hasthe storage capacitance line circuit electrically connected to the otherconnection via the COM terminal (not shown).

The current detecting circuit 13 detects the electric current flown inthe transparent conductive film 12 during a position detecting period.Signals regarding the electric currents detected by the currentdetecting circuit 13 are outputted towards a position detecting circuit(not shown). The position detecting circuit determines a touchedposition touched by a finger (contact mean) 24 on the glass substrate 23based on the output signals from the current detecting circuit 13.

The AC voltage source 22 supplies AC voltages to the transparentconductive film 12 via the corresponding current detecting circuit andthe linearization pattern 30 a.

FIG. 2 is a plan model illustration showing a relation between thelinearization pattern sections and an anisotropic conductor according tothe first exemplary embodiment of the invention. FIG. 3 is a fragmentarysectional view taken along I-I′ line of FIG. 2. In all the drawings, itis assumed that the plan model illustrations are viewed from the countersubstrate (front face of the display device) side.

However note that the plan model illustration of FIG. 2 does not containa counter substrate, and the fragmentary sectional view of FIG. 3contains a counter substrate. In the drawings of FIG. 2 and thereafter,the structures other than the linearization pattern sections 30 areomitted appropriately unless there is any specific notification, inorder to provide explanations by specifically placing the emphasis onthe relation between the linearization pattern sections 30 and thedisplay device as well as the features of the exemplary embodiment.

Referring to the plan model illustration of FIG. 2 and the fragmentarysectional view of FIG. 3, an anisotropic conductor 34 as an example of aconductive member is formed between the transparent conductive film 12and the linearization pattern sections 30 on the display devicesubstrate 10. This anisotropic conductor 34 electrically connects thelinearization pattern sections 30 on the display device substrate 10with the transparent conductive film 12 (configures an conductiveimpedance surface). The pattern of the anisotropic conductor 34 isformed in a frame shape so as to cover the whole linearization patternsections 30 provided in the outer peripheral area of the display devicesubstrate 10.

The anisotropic conductor 34 is an insulating adhesive in whichparticles of a metal such as nickel or fine particles obtained bycoating a metal such as nickel or gold to plastics are dispersed. Whenthe anisotropic conductor 34 is inserted between the electrodes of twosubstrates, and heat/pressure is applied thereto, the metal particles ofthe anisotropic conductor 34 electrically connect each of theelectrodes. This makes it possible to connect the electrodes on the topand bottom electrically, to insulate the neighboring pixels, and tocouple the top and bottom electrodes adhesively.

As will be described later by referring to FIG. 5, the linearizationpattern sections 30 are formed with a same layer as the pixel electrode5. As shown in FIG. 5, the pixel electrode 5 comprises a laminated layer“ITO 40/AL 42” that is formed with AL (aluminum) 42 and an ITO (indiumtin oxide: transparent conductive film) 40 stacked on the AL (aluminum)42, for example.

Similarly, as shown in FIG. 3, the linearization pattern sections 30comprise a laminated layer “ITO 40/AL 42” that is formed with the AL(aluminum) 42 and the ITO (transparent conductive film) 40 stacked onthe AL (aluminum) 42, for example.

Now, effects of a partial resistance decrease in the transparentconductive film achieved by the linearization pattern sections 30 willbe described.

In general, the resistance of the area with the linearization patternsection 30 is lower than the resistance of the transparent conductivefilm which configures the impedance surface (low resistance part shownin FIG. 3).

The resistance of the area with the linearization pattern section can beconsidered as a synthesized resistance in which the resistance of thetransparent conductive film and the resistance of the linearizationpattern section are connected in parallel. Therefore, it becomes lowerthan the resistance of the transparent conductive film regardless of theextent of the resistance of the linearization pattern section.

In the meantime, the counter substrate 19 has a glass substrate 23 ofthe counter substrate 19, a color filter (not shown) formed on thesurface of the liquid crystal 2 side, and the transparent conductivefilm 12 formed on the surface of the color filter on the liquid crystal2 side. The transparent conductive film 12 is a counter electrode formedwith ITO (indium tin oxide), which comprises a conductive impedancesurface.

Further, a polarizing plate (not shown) is provided on outer surface ofthe glass substrate 23. The liquid crystal 2 is an example of a displayelement (pixel) capable of performing electro-optic response providedbetween the display device substrate 10 and the counter substrate 19.The liquid crystal 2 is sealed by a sealing device such as a sealingagent 36 that is an example of a seal.

The linearization pattern sections 30 (30 a, 30 b) can make distributionof electric field lines on the impedance surface uniform. Various kindsare designed as the linearization pattern sections 30, and FIG. 2 showsan example thereof. In the distribution of the electric field lineswhile ideal linearization can be achieved, straight equipotential linescan be distributed at equivalent intervals.

Now, the structure of the first exemplary embodiment shown in FIG. 2 iscompared with the structure of a touch panel to which linearizationpattern sections of a related technique depicted in Patent Document 2 orthe like are provided.

FIG. 18 is a plan model illustration of a touch panel with a touchsensor to which the linearization pattern sections of the relatedtechnique are provided. FIG. 19 is a fragmentary sectional view alongV-V′ line of FIG. 18.

Referring to FIG. 18 and FIG. 19, a quartz substrate 80 as a countersubstrate is covered by a transparent conductive film 81. Linearizationpattern sections 82 formed with silver paste or the like are formed inthe outer periphery on the transparent conductive film 81.

In the meantime, with the first exemplary embodiment shown in FIG. 2,the linearization pattern sections 30 are formed on the display devicesubstrate 10 without an additional step in the display device substrateforming process.

And the conductive member is possible to reduce the resistance in apartial area of the opposing conductive impedance surface by having itcorresponded to the pattern of the linearization pattern sectionsthrough electrically connecting the linearization pattern sections onthe display device substrate and the conductive impedance surface of thecounter substrate. It can be considered as if the linearization patternsections formed on the display device substrate are projected upon theconductive impedance surface on the counter substrate.

The above arrangement is unnecessary to form the linearization patternsections (reference numeral 82 in FIG. 18) on the transparent conductivefilm 12 of the counter substrate, since the linearization patternsections 30 also function as those sections.

Therefore, it is possible to realize the same function of thelinearization pattern sections upon the conductive impedance surface ofthe counter substrate without forming the linearization pattern sectionson the counter substrate side.

Further, it is possible to decrease the resistance of a partial area ofthe impedance surface by corresponding to the shape of the linearizationpattern. It can be considered as if the linearization pattern sectionsformed on the display device substrate are projected upon the conductiveimpedance surface.

Furthermore, areas used specifically for forming the linearizationpattern sections on the counter substrate side become unnecessary.

FIG. 2 shows a simplified example of the linearization pattern sections30. While the linearization pattern sections 30 a, 30 b of the displaydevice 100 shown in FIG. 4 are more complicated than the pattern shownin FIG. 2, more uniform voltages can be supplied from the four sides ofthe outer periphery of the transparent conductive film 12.

Specifically, the linearization pattern sections 30 b (second patternsections) shown in FIG. 4 include first short inner-periphery sidepatterns 30 b-4 on the inner-periphery side, second inner-periphery sidepatterns 30 b-3 longer than the first inner-periphery side patterns 30b-4, third inner-periphery side patterns 30 b-2 longer than the secondinner-periphery side patterns 30 b-3, and geometrical shape patterns 30b-1 of a specific geometrical shape extended along one end side of eachpattern from the inner-periphery side towards the outer-periphery side.The linearization pattern sections 30 a (first pattern sections) areformed by being extended long towards the center.

In the followings, explanations regarding operations will be provided byreferring to the simplified structure of the linearization patternsections 30 as in FIG. 2 except for the structure shown in FIG. 4.

(Operations)

Now, operations of the display device according to the first exemplaryembodiment will be described by referring to FIG. 1 and FIG. 6. FIG. 6is a timing chart which schematically shows a state of voltages of mainelectrodes of the display device according to the first exemplaryembodiment of the present invention.

In FIG. 6, Vc is a voltage of the transparent conductive film (referencenumeral 12 of FIG. 1), Vg is a voltage of the scanning line (referencenumeral 6 of FIG. 1), and SW is a voltage of a control signal whichdetermines the state of the switch (reference numeral 21 of FIG. 1).While FIG. 6 schematically shows a case of having two signal lines, thenumber thereof can be designed arbitrarily.

Regarding to drive the display device, the display device has twoperiods of a display drive period and a position detecting period. Thosetwo periods are divided in terms of time base. The display drive periodis a period for writing a voltage for achieving pixel to display animage. The position detecting period is a period where the currentdetecting circuit (reference numeral 13 of FIG. 1) detects the electriccurrent in order to determine the position of a finger or a pen and todetect whether or not there is a pointing action.

A vertical blanking period is used for the position detecting period.The vertical blanking period is a period where the scanning operationusing the scanning line (reference numeral 6 of FIG. 1) is not executed(FIG. 1 is referred for explanation). Further, the switch 21 connectsthe wiring 32 to the COM wiring in the display drive period. Meanwhile,in the position detecting period, the switch 21 is made conductive withthe AC voltage source 22 side including the current detecting circuit13. This state can be achieved by setting SW signal of FIG. 6 to B,i.e., by setting the SW signal to high level.

In such switch state (i.e., in the state of the switch 21 shown in FIG.1), same-phase and same-potential AC voltages generated by the ACvoltage source 22 are applied to the linearization pattern sections 30 avia the wirings 32. Note here that the linearization pattern sections 30are electrically connected to the transparent conductive film 12 via theanisotropic conductor 34.

The AC voltages generated by the AC voltage source 22 are applied to theareas in the vicinity of the four corners of the transparent conductivefilm 12 via the electrically connected linearization pattern sections 30a. The voltage of the transparent conductive film 12 is expressed as Vcin the position detecting period of FIG. 6.

As described, the AC voltages are supplied uniformly from the vicinityof the four corners of the transparent conductive film 12. When thesurface of the LCD is touched by the finger 24 as an example of thecontact mean, a capacitance 25 is formed between the finger 24 and thetransparent conductive film 12 in the area that corresponds to thetouched part. At this time, a potential of the user is grounded via thefinger 24, so that there is a potential difference generated between thefinger 24 and the AC voltage source 22. Thus, an electric current flowsvia the capacitance 25 from the touched position to the vicinity of thefour corners through the transparent conductive film 12.

In the meantime, while each of the linearization pattern sections 30 bis isolated on the display device substrate 10, each of those is incontact with the anisotropic conductor 34 and electrically connected tothe transparent conductive film 12 via the anisotropic conductor 34.

The linearization pattern sections 30 b decrease the resistance in thecorresponding area of the transparent conductive film 12. Therefore, theouter-peripheral area of the transparent conductive film 12 can be keptto the same potential, even if the potential of the transparentconductive film 12 in the area corresponding to the touched positionbecomes lowered because of the capacitance coupling caused when thefinger 24 touches the surface of the LCD.

There are voltage drops generated in the outer-peripheral area withrespect to the AC voltage sources 22 in the vicinity of the four cornersof the transparent conductive film 12. However, the resistance from thevicinity of the four corners of the transparent conductive film 12 to anarbitrary point of the outer-peripheral area is adjusted by thelinearization pattern sections 30 b and the like to make the voltagedrops at the arbitrary point of the outer-peripheral area uniform.

The resistance from the areas of the vicinity of the four corners to anarbitrary point on a neighboring side is adjusted by combining a lowresistance area where the linearization pattern section 30 b is providedand a high resistance area where the linearization pattern section 30 bis not provided.

At this time, signals corresponding to the electric currents Ia, Ib, Ic,Id detected by the four current detecting circuits 13 are calculated todetect the presence of a touch by the finger and the positioncoordinates (x,y) thereof.

Examples of the calculations may be expressed as following Expression 1and Expression 2.x=(Ic+Id)/(Ia+Ib+Ic+Id)k1+k ₂  Expression 1y=(Ib+Ic)/(Ia+Ib+Ic+Id)k ₁ +k ₂  Expression 2

Note here that “x” is the X coordinate of the touched position, and “y”is the Y coordinate of the touched position. Further, “k₁” and “k₂” areinvariables, and Ia, Ib, Ic, Id are the electric currents detected bythe four current detecting circuits 13.

As described above, the transparent conductive film 12 functions as atransparent conductive film of a static capacitive touch sensor duringthe position detecting period.

(Manufacturing Method)

Next, various kinds of processing procedures as the manufacturing methodof the display device having the above-described structures (displaydevice manufacturing method) will be described by referring to FIG. 5.FIG. 5 is a sectional view which schematically shows an example of thedisplay device for describing the display device manufacturing methodaccording to the first exemplary embodiment of the invention. While ablack matrix 58 and an overcoat layer 54 are illustrated in FIG. 5,those are omitted in the other drawings.

The display device manufacturing method according to the exemplaryembodiment is directed to a structure which can perform displays byhaving a display element capable of performing electro-optical responseformed between conductible first and second substrates, and can detect acontact position touched by a contact body by having a conductiveimpedance surface formed on the second substrate side.

As the basic structure, the display device manufacturing method caninclude: a first step which forms, on the first substrate, alinearization pattern section including a plurality of electrodescapable of performing linearization of an electric field on theconductive impedance surface and capable of detecting an electriccurrent on the conductive impedance; a second step which forms, on thesecond substrate, a counter substrate functioning as the conductiveimpedance surface; and a third step which forms a conductive memberbetween the linearization pattern sections and the counter electrode.

Note here that the conductive impedance surface is a surface where anelectric field curve distribution (potential distribution) is formed onthe transparent conductive film, when voltages are applied to thetransparent conductive film from the vicinity of the four corners.

Further, linearization of the electric field is to form equipotentiallines in parallel to each side of the outer periphery in such a mannerthat the intervals between the equipotential lines become uniform (tokeep the linearity and the orthogonal of the electric fields).

Therefore, it becomes possible to perform linearization of the electricfields of the conductive impedance surface by the use of thelinearization pattern sections.

Further, the first step can be executed simultaneously with a step forforming the pixel electrode on the first substrate or a step for formingthe wirings on the first substrate.

Furthermore, the first step can include a series of steps for forming aconductive film, performing PR, and performing etching.

More specifically, the manufacturing method (first step) of the displaydevice substrate 10 (first substrate) will be described by referring toa case of a low-temperature polysilicon TFT. That is, the display devicesubstrate 10 (first substrate) can be formed with a TFT substrate.

As the basic structure of TFT, employed is a coplanar type having a gateelectrode formed higher than a channel polysilicon, and the conductivetype is an n-channel type which uses electrons as carries of the channelelectric current.

Referring to FIG. 5, the glass 23 (transparent substrate) of the displaydevice substrate 10 is covered by a silicon oxide film 46 a, and apolysilicon film 48 is formed thereon in an island form.

Here, a V-group element such as phosphor is doped in the areas of thepolysilicon film to be a drain area 49 a and a source area 49 b.

Further, even though not shown, LDD (lightly doped drain) to which asmaller amount of phosphor than that of the source/drain areas isintroduced may be provided between the channel area and the source/drainareas.

With the LDD-structure TFT, concentration of the electric fields on theboundary of the drain can be eased by making the gradient of theimpurity concentrations from the channel to the drain gradual throughproviding a low-concentration impurity area in the boundary between thechannel and the drain. Thus, a leak current suppressing effect can beachieved.

The island-form polysilicon film 48 is covered by a silicon oxide film46 b, and a gate electrode 52 is formed thereon. Note here that thesilicon oxide film 46 b in the area sandwiched between the polysiliconfilm 48 and the gate electrode 52 serves as a gate insulating film.

Further, a storage capacitance (not shown) may be formed by the siliconoxide film 46 b. A silicon oxide film 46 c covers the gate electrode 52.The gate electrode 52, the drain area 49 b, and the source area 49 b areopened by forming contact holes in the silicon oxide film 46 c.

The AL (aluminum) 42 is sputtered on the silicon oxide film 46 c, and aresist mask is remained in the areas to be the signal line (electrode),the pixel electrode 5, and the linearization pattern sections 30 (notshown). Thereafter, the AL (aluminum) 42 is dry-etched to performpatterning.

An interlayer insulating film 41 is formed on the AL (aluminum) 42. Thisinterlayer insulating film 41 is configured with stacked layers of asilicon nitride film and an acryl film. Through forming contact holes inthe interlayer insulating film 41, the signal line (electrode), thepixel electrode 5, and the linearization pattern sections 30 are opened.At last, after sputtering the ITO (transparent conductive film) 40, theITO (transparent conductive film) 40 is etched except the ITO(transparent conductive film) 40 configuring the source electrode andthe ITO (transparent conductive film) 40 configuring the linearizationpattern sections 30 to complete the display device substrate. Thelinearization pattern sections 30 are configured with stacked layers of“ITO 40/AL 42”.

As described, the linearization pattern sections 30 (30 a, 30 b) areformed by a conductive film that is the same layer of a single layer ofconductive film or a plurality of layers of conductive films whichconfigure the pixels or the peripheral circuits on the first substrate(display device substrate).

The case of the n-type channel has been described above. In a case ofp-channel type, “p” and “n” may simply be switched. Further, both then-channel type and the p-channel type may be used as well.

The scanning line driving circuit 14 and the signal line driving circuit15 can be formed by using the n-type TFT and the p-type TFT.

Further, while the display device substrate 10 is formed by alow-temperature polysilicon TFT process in the first exemplaryembodiment, the display device substrate 10 may also be formed by anamorphous silicon TFT process.

Furthermore, the display device substrate 10 may also be formed by otherTFT process such as a micro crystal silicon TFT process, an oxide TFTprocess, an organic TFT process, or a process which forms TFT aftertransferring a silicon thin film on a supporting substrate.

Further, after forming a circuit by using the polysilicon TFT process,the amorphous silicon TFT process, a bulk silicon process, an SOIprocess, or the like, it may be transferred to another substrate to formthe display device substrate 10.

Next, a method (second step) for forming the counter substrate 19 willbe described.

As a pixel part, color filters are provided in matrix (not shown) on theglass 23 (transparent substrate) of the counter substrate 19. Theeffective aperture part of the pixel part is limited because of thewirings and the gaps therebetween, the black matrix 58, and the like.The color filters and the black matrix 58 are covered by the overcoatlayer 54 formed with acryl or the like, and the transparent conductivefilm 12 is formed on the overcoat layer 54. Further, an alignment filmformed with polyimide or the like (not shown) is printed on thetransparent conductive film 12.

Next, a third step will be described. In this step, a TFT-LCD panel isformed by combining the above-described display device substrate 10 andthe counter substrate 19. Further, the liquid crystal is filled betweenthe display device substrate 10 and the counter substrate 19 on thepixel TFT side that is the right side of FIG. 5.

In the meantime, on the linearization pattern section 30 side that isthe right side of FIG. 5, the anisotropic conductor 34 is in contactwith the ITO (transparent conductive film) 40 of the display devicesubstrate 10 and the transparent conductive film 12 on the countersubstrate.

While there has been described by referring to a case of atransmissive-type LCD which displays images by modulating surfacebacklight from a back side with the LCD, the embodiment can be appliedalso to a reflective-type LCD which utilizes peripheral light fordisplay by forming a metal electrode to be a reflection plate on theabove-described display device substrate 10. Further, the embodiment canalso be applied to a transflective-type LCD used for both transmissionand reflection types by forming minute dot-like holes in a net form onthe reflection plate.

While the first exemplary embodiment uses glass as the base material forthe glass substrate 23 and the display device substrate 10, it is alsopossible to use a flexible material. In that case, the transparentconductive film 12 used for detecting positions is formed in the countersubstrate 19 in a unified manner. Thus, mechanical distortion is noteasily generated by a bending stress, and the position detectingperformance is not deteriorated by the bend.

(Effects)

As described above, it is possible with the first exemplary embodimentto provide a display device with a built-in touch sensor, which issuited for reducing the weight, the size, and the thickness, and also iscapable of accurately detecting the position touched by the finger.

Further, the first exemplary embodiment does not require an additionalstep for forming the linearization pattern sections 30 on the countersubstrate 19, and also does not require the special manufacturing deviceand resources for the additional step. As a result, the manufacturingcost of the display device can be decreased.

That is, it is unnecessary to add a new step, when the linearizationpattern sections 30 are formed simultaneously in any of the steps forforming the electrodes or the wirings on the display device substrate.Further, when the step for forming the electrodes or the wirings and thelinearization patterns is configured with a series of steps (referred toas PR step hereinafter) for forming a conductive film, performing PR(photolithography), and performing etching, those can be achieved withthe same step for forming the display pixels and the like. Therefore, itis unnecessary to specifically add the steps for forming linearizationpattern sections. The linearization pattern sections may simply be addedto the layout of the photo mask and the like.

Further, with the first exemplary embodiment, the pattern can be formedin a highly accurate manner by the PR step than the case of othermethods such as screen printing. That is, the linearization patternsections can be made in a highly precise pattern for precise positioningthrough forming the linearization pattern sections on the display devicesubstrate through the PR step. As a result, it becomes easy to employstill thinner lines, so that detecting accuracy of the positions touchedby the finger or the pen can be improved. At the same time, it ispossible to reduce the area occupied by the linearization patternsections 30, thereby making it possible to provide a narrow-frame LCD.

Furthermore, it is possible with the first exemplary embodiment toreduce the resistance of the linearization pattern sections 30 stillmore by using a material that has low sheet resistance for thelinearization pattern sections 30. Particularly, it is preferable to useAL (aluminum) or AL (aluminum) alloy instead of silver.

Further, through forming the linearization pattern sections 30 with thesame layer as that of the pixel electrode 5, the contact resistancebetween the linearization pattern sections 30 and the anisotropicconductor 34 can be reduced. This is because the ITO (transparentconductive film) 40 is in contact between the anisotropic conductor 34and the same layer as that of the signal line (electrode) 4 of the pixelelectrode 5, and the ITO (transparent conductive film) 40 exhibits afine contact property for both the material of the signal line(electrode) 4 and the anisotropic conductor 34, thereby having lowresistance.

Practically, the linearization pattern sections 30 were formed with thesame layer as that of the pixel electrode 5, and each area of thepattern of the ITO (transparent conductive film) 40 for forming thelinearization pattern section 30 was designed as 1 mm². The resistancebetween the ITO (transparent conductive film) 40 and the transparentconductive film 12 via the anisotropic conductor 34 in that case was assmall as 1Ω.

As described above, the contact resistance between the linearizationpattern sections 30 on the display device substrate 10 and theanisotropic conductor 34 is reduced, which can provide an effect ofgreatly reducing the resistance in the specific areas of the transparentconductive film 12.

Further, the anisotropic conductor (conductive member), is possible toreduce the resistance in a partial area of the opposing conductiveimpedance surface by having it corresponded to the pattern of thelinearization pattern sections through electrically connecting thelinearization pattern sections on the display device substrate and theconductive impedance surface. It can be considered as if thelinearization pattern sections formed on the display device substrateare projected upon the conductive impedance surface on the countersubstrate.

Now, the corresponding relation between the structural elements of theexemplary embodiment and the structures of the present invention will bedescribed. The display device of the present invention is capable of:performing displays by having a display element (reference numeral 2shown in FIG. 1, for example) capable of performing electro-opticalresponse formed between the conductible first and second substrates; anddetecting contact positions touched by a contact body through detecting,at a plurality of points, electric current values flowing on theconductive impedance surface formed on the second substrate (referencenumeral 10 or the like shown in FIG. 1, for example). This displaydevice includes the linearization pattern sections 30 (structuresconfigured with reference numerals 30 a, 30 b shown in FIG. 1, forexample) formed on the first substrate (reference numeral 10 shown inFIG. 1, for example) side, and a conductive member (reference numeral 34shown in FIG. 1, for example) which electrically connects thelinearization pattern sections and the conductive impedance surface.

Further, the display device can display images by forming the displayelement capable of performing electro-optical responses between thefirst and second substrates by using a sealing device. The secondsubstrate can detect the touched positions by having the conductiveimpedance surface formed thereon and measuring, at a plurality ofpoints, the electric current values flown at the contact point touchedby the contact body. The first substrate opposes against the conductiveimpedance surface, and the linearization pattern, the control part ofthe display element, and the wirings can be formed thereon.

As an exemplary advantage according to the invention, it becomesunnecessary to form the linearization pattern sections on the secondsubstrate through forming the linearization pattern sections on thefirst substrate side. Thus, no special manufacturing device andresources are required. Therefore, it is possible to provide a displaydevice and the like with a small occupied area of the linearizationpattern sections in reduced weight, size, and thickness, which candetect the positions touched by the contact body accurately whilereducing the cost for manufacturing the display devices.

Second Exemplary Embodiment

Next, a second exemplary embodiment of the invention will be describedby referring to FIG. 7. Hereinafter, the practically same structuralelements as those of the first exemplary embodiment are omitted, andonly different points will be described. FIG. 7 is a plan modelillustration showing an example of a schematic structure of a displaydevice according the second exemplary embodiment of the invention.

In the above-described first exemplary embodiment, the anisotropicconductor and the sealing agent are different structural elements.However, the second exemplary embodiment employs a structure where theanisotropic conductor also functions as the sealing agent. That is, itis a case where the conductive member is inserted between the firstsubstrate and the second substrate to function as the sealing agent forsealing the display element.

Specifically, as shown in FIG. 7, in a display device 200 according tothe second exemplary embodiment, linearization pattern sections 30 on adisplay device substrate 10 and a transparent conductive film 12 areelectrically connected via an anisotropic conductor 34, as in the caseof the first exemplary embodiment (FIG. 2). A difference with respect toFIG. 2 is that the display device substrate 10 and a counter substrate19 are adhesively laminated via the pattern of the same anisotropicconductor 34 in order to connect those electrically and to seal a liquidcrystal 2 at the same time.

As the anisotropic conductor 34, it is preferable to use a sealing agentin which conductive particles are mixed. An epoxy resin is used as thesealing agent, and gold balls or the like are used as the conductiveparticles. Further, as a method for laminating the substrates via theseal, the sealing agent is applied to a sealing part of one of thesubstrates to adhesively stick the substrates with each other when thesubstrates are laminated. Thereafter, the substrates are sintered toperform thermosetting of the sealing agent.

Described now is the effect of the anisotropic conductor 34 whichelectrically connects the linearization patterns 30 and the transparentconductive film 12 and seals the liquid crystal 2 at the same time.

The first exemplary embodiment (FIG. 2) has the anisotropic conductor 34which electrically connects the linearization pattern sections 30 on thedisplay device substrate 10 and the transparent conductive film 12, andhas the sealing agent 36 for sealing the liquid crystal 2 as separatepatterns. With this structure, the pattern of the anisotropic conductor34 and that pattern of the sealing agent 36 occupy large areas. Thisresults in raising a new issue, such as expanding the frame area of theLCD.

In the meantime, with the structure of FIG. 7, the pattern (referencenumeral 36 of FIG. 2) of the sealing agent 36 can be omitted byelectrically connecting the linearization pattern sections 30 on thedisplay device substrate 10 and the transparent conductive film (notshown) and by sealing the liquid crystal 2 at the same time with thepattern of the anisotropic conductor 34 which also has a function of thesealing agent. Thus, the area that may otherwise be occupied by thesealing agent 36 can be decreased. As a result, the frame of the LCD canbe narrowed.

Other structures, steps, functions, and operational effects thereof arethe same as those of the above-described exemplary embodiment. Further,it is also possible to put the processing contents of the manufacturingdevice used for the method for manufacturing through each of the stepsdescribed above, the structural elements of each part (circuit), andeach function thereof into programs to have those programs executed by acomputer.

Third Exemplary Embodiment

Next, a third exemplary embodiment of the invention will be described byreferring to FIG. 8 and FIG. 9. Hereinafter, the practically samestructural elements as those of the first exemplary embodiment areomitted, and only different points will be described. FIG. 8 is a planmodel illustration showing an example of a schematic structure whichillustrates a relation between linearization pattern sections and ananisotropic conductor of a display device according to the thirdexemplary embodiment of the invention. FIG. 9 is a fragmentary sectionalview showing a II-II′ part of FIG. 8.

In this exemplary embodiment, the layout pattern of the conductor as anexample of the conductive member is formed to correspond to the layoutpattern of the linearization pattern sections. That is, it is a casewhere the conductive member is formed to have a pattern of a pluralityof divided sections, and the conductive member pattern has the samelayout pattern as that of the linearization pattern sections.

Specifically, as shown in FIG. 8, in a display device 300 of thisexemplary embodiment, the layout of the pattern of a conductor 47 whichelectrically connects linearization pattern sections 30 on a displaydevice substrate 10 and a transparent conductive film 12 is formed tocorrespond to the layout of the linearization pattern sections 30. Theconductor 47 may be of an isotropic type or an anisotropic type.

More specifically, since the layout of the pattern (conductor pattern)of the conductor 47 is formed to be same as that of the linearizationpatterns 30 on the display device substrate 10, the pattern of theconductor 47 comes to have a set of a plurality of divided conductors47, and neighboring conductors 47 are not electrically connected. Here,the liquid crystal 2 is sealed by the sealing agent 36.

Further, the pattern of the conductors 47 is in the same layout as thatof the linearization pattern sections 30, so that the reference numerals47 overlap with the reference numerals

-   -   (30 a, 30 b) in the plan model illustration shown in FIG. 8. The        fragmentary sectional view of FIG. 9 shows a laminated structure        of the part shown indicated by reference numeral 30 (30 a, 30 b)        and the part indicated by reference numeral 47.

It is preferable to form the conductors 47 with post (cylindrical)spacer or the like, for example. Normally, spacer is spherical bodieswith a uniform particle diameter or cylinders with a uniform diameter.In the display part, the spacer functions to keep the thickness (cellgap) between the display device substrate 10 and the counter substrate19 on the black matrix of the counter substrate 19.

Normally, the post spacer is an insulator using glass or plastics as amaterial. However, a conductive material is used in this case toelectrically connect the display device substrate 10 with the countersubstrate 19.

Next, the effect of the pattern of the conductors 47 designed tocorrespond to the linearization pattern sections 30 will be described.

The linearization pattern sections 30 on the display device substrate 10and the transparent conductive film 12 can be electrically connected viathe conductors 47. However, the areas where the resistance of thetransparent conductive film 12 is reduced depend on the pattern of theconductors 47.

Thus, when the pattern of the conductors 47 is formed in a singlepattern which covers all the linearization pattern sections 30 on thedisplay device substrate 10 as in the case of the first exemplaryembodiment (FIG. 2), the conductors 47 are electrically connected to thesurface that is in parallel to the film surface if the conductors 47 areelectrically isotropic. Therefore, the areas of the transparentconductive film 12 where the resistance is reduced are to depend on thepattern of reference numeral 34 shown in FIG. 2.

Thus, the pattern of the conductors 47 is formed to correspond to thelinearization pattern sections 30, so that the neighboring conductors 47are not electrically connected to each other. In this case, theconductors 47 do not have to be electrically anisotropic but may beisotropic as well.

As described above, it is possible with this exemplary embodiment toachieve an effect of reducing the resistance in a desired area of thetransparent conductive film 12 even with the use of the electricallyisotropic conductors 47 that are electrically isotropic, while achievingthe same operational effects as those of the first exemplary embodiment.Since it is not necessary for the conductors to be electricallyanisotropic, ranges of selections regarding the conductor materials canbe expanded. Therefore, it is possible to select a low-price material.

Further, by using the conductors 47 as the post spacer, it becomespossible to form the conductors 47 by the same step that is performedfor forming the post in order to keep the gap between the display devicesubstrate 10 and the counter substrate 19 within the substrate planeuniform. As a result, it becomes unnecessary to add a new step, therebymaking it possible to reduce the cost for manufacturing the displaydevices.

Other structures, steps, functions, and operational effects thereof arethe same as those of the above-described exemplary embodiment. Further,it is also possible to put the processing contents of the manufacturingdevice used for the method for manufacturing through each of the stepsdescribed above, the structural elements of each part (circuit), andeach functions thereof into programs to have those programs executed bya computer.

Fourth Exemplary Embodiment

Next, a fourth exemplary embodiment of the invention will be describedby referring to FIG. 10 and FIG. 11. Hereinafter, the practically samestructural elements as those of the first exemplary embodiment areomitted, and only different points will be described. FIG. 10 is a planmodel illustration showing an example of a schematic structure whichillustrates a relation between linearization pattern sections and ananisotropic conductor of a display device according to the fourthexemplary embodiment of the invention. FIG. 11 is a fragmentarysectional view showing a III-III′ part of FIG. 10.

This exemplary embodiment employs a structure in which the linearizationpattern sections provided separately in the vicinity of the four cornersof the display device substrate are formed long. That is, this is a casewhere the linearization pattern sections are formed in the corners ofthe first substrate, and the linearization pattern sections include thefirst pattern sections (30 a) which are connected to the wiring part towhich position detecting voltages are supplied, and the second patternsections (30 b) which are formed on the side areas of the firstsubstrates, and not connected to the wiring part. The first patternsections are extended from the corners towards the side areas.

Specifically, as shown in FIG. 10, in a display device 400 according tothe fourth exemplary embodiment, linearization pattern sections 30 on adisplay device substrate 10 and a transparent conductive film 12 areelectrically connected via an anisotropic conductor 34, and a liquidcrystal 2 is sealed with the same anisotropic conductor pattern 34, asin the case of the second exemplary embodiment (FIG. 7). However, it isdifferent from the second exemplary embodiment (FIG. 7) in terms of thelayout of the linearization pattern sections 30.

More specifically, the linearization pattern sections 30 a providedseparately in the vicinity of the four corners of the display devicesubstrate 10 are formed to extend towards the centers of the neighboringsides thereof. That is, the linearization pattern section 30 a (firstpattern section) is formed to extend from the corner to the side part inan extending range from the corner to the vicinity of the center of theside.

A wiring 32 is connected to the linearization pattern sections 30 a.This wiring 32 is connected to an AC voltage source 22 (not shown).

Further, as shown in 10, dummy patterns 39 insulated from an Al(aluminum) electrode 42 via an insulating layer 41 may be provided inthe four sides of the outer peripheral area of the display devicesubstrate 10, instead of providing the linearization pattern sectionsdivided into a plurality of sections on the display device substrate 10.

The linearization pattern sections 30 are in contact with theanisotropic conductor 34 and electrically connected to the transparentconductive film 12 via the anisotropic conductor 34. However, the dummypatterns 39 are covered by the insulating layer 41 and not in contactwith the anisotropic conductor 34, so that the dummy patterns 39 are notelectrically connected to the transparent conductive film 12.

It is preferable for the dummy patterns 39 to be formed by using thesame layer as that of the linearization pattern sections 30.

As shown in FIG. 10, the linearization pattern section 30 a is extendedfrom the vicinity of the four corners of the display device substrate 10towards the centers of the neighboring sides, and there are areas in thevicinity of the center of the sides where no linearization patternsection 30 a is provided.

Therefore, compared to the areas where the linearization patternsections 30 a are provided, there are recessed areas generated on thedisplay device substrate 10 in the areas having no linearization patternsection 30 a, because of the thickness of the linearization patternsection 30 a. This results in having the locally large gap generatedbetween the display device substrate 10 and the counter substrate 19.

Therefore, the dummy patterns 39 are provided in the areas having nolinearization pattern sections 30 a, which provides as effect ofimproving the uniformity of the gap of the LCD.

Specifically, the pixel electrode (reference numeral 5 in FIG. 5) or thelike is used. As shown in FIG. 11, the dummy pattern 39 is configuredwith layers of the AL (aluminum) 42, the insulating layer 41 (interlayerinsulating film), and an ITO (transparent conductive film) 40. That is,the dummy pattern 39 as an example of the second pattern section canhave a plurality of layers of conductive films configuring the pixel andthe peripheral circuit formed on the display device substrate 10, andthe interlayer insulating film between the plurality of the conductivefilms. Silicon nitride, acryl, or the like is used for the insulatinglayer 41 covering the dummy pattern 39. Further, no contact hole isformed in the areas of the insulating layer 41 corresponding to thedummy patterns 39.

Furthermore, the second pattern sections can be omitted as well.

Next, described are the operations of the linearization pattern sections30 a which are provided in the vicinity of the four corners of thedisplay device substrate 10 by being extended towards the centers of theneighboring sides.

During the position detecting period for detecting the position touchedby the finger or the pen, the electric currents flown in the transparentconductive film 12 are detected by a current detecting circuit(reference numeral 13 in FIG. 1) on an external substrate (referencenumeral 20 in FIG. 1) via the anisotropic conductor 34 and thelinearization pattern sections 30 a.

In the meantime, during the display drive period, a common voltage isapplied to the linearization pattern sections 30 a via the anisotropicconductor 34 to keep the transparent conductive film 12 to the commonpotential. Then, the voltage of the signal line (electrode: referencenumeral 4 in FIG. 4) is applied from the display device substrate 10side and the common voltage is applied from the counter substrate to theliquid crystal 2 to change the light transmittance of the liquid crystal2.

To extend the linearization pattern sections 30 a towards the centers ofthe respective neighboring sides can provide an effect of reducing theresistance on the four sides of the outer periphery of the transparentconductive film 12.

The areas of the lowered resistance depend on the extended range of thelinearization pattern sections 30 a from the vicinity of the fourcorners towards the centers of the neighboring sides. The linearizationpattern section 30 a can be extended to the vicinity of the center ofthe sides as long as it does not reach other linearization patternsection 30 a.

As described above, it is possible with this exemplary embodiment toachieve an effect that is the same effect obtained by providing theplurality of divided linearization pattern sections 30 a on the foursides of the outer periphery of the display device substrate 10, whileachieving the same operational effects as those of the exemplaryembodiments described above.

Further, while the linearization pattern sections (reference numeral 30b in FIG. 7) are formed in a double structure, the linearization patternsections 30 a in the structure of the fourth exemplary embodiment areformed in a single structure. Therefore, the occupying area can bereduced.

As a result, it is possible to achieve an effect of narrowing the frameof the LCD.

Other structures, steps, functions, and operational effects thereof arethe same as those of the above-described exemplary embodiment. Further,it is also possible to put the processing contents of the manufacturingdevice used for the method for manufacturing through each of the stepsdescribed above, the structural elements of each part (circuit), andeach functions thereof into programs to have those programs executed bya computer.

Fifth Exemplary Embodiment

Next, a fifth exemplary embodiment of the invention will be described byreferring to FIG. 12 and FIG. 13. Hereinafter, the practically samestructural elements as those of the first exemplary embodiment areomitted, and only different points will be described. FIG. 12 is a planmodel illustration showing an example of a schematic structure of adisplay device according to the fifth exemplary embodiment of theinvention. FIG. 13 is a perspective view showing the potentialdistribution of a transparent conductive film.

This exemplary embodiment employs a structure where the touched positiondetecting period is divided for a position x (direction) and a positiony (direction).

Specifically, as shown in FIG. 12, in a display device 500 according tothe fifth exemplary embodiment, linearization pattern sections 30 on adisplay device substrate 10 and a transparent conductive film (counterelectrode) are electrically connected via an anisotropic conductor 34,as in the case of the fourth exemplary embodiment (FIG. 10). However, itis different from the fourth exemplary embodiment in respect that thefifth exemplary embodiment performs a control for dividing the detectingperiod for the position x (direction) and the position y (direction)during the detecting period of a finger touched position 26.

The circuit part shown in FIG. 12 illustrates a switching state duringthe position detecting period for the x direction of the finger.

More specifically, during the detecting period of the finger touchedposition 26, the display device 500 connects the linearization patternsections 30 a provided between the vicinity of the four corners of thedisplay device substrate to current detecting circuits 13 via a currentdetecting direction change over switch 521.

In the period for detecting the position x (x direction that is a firstdirection), the display device 500 connects the linearization patternsections 30 a (lower-left section: first electrode, upper-left section:second electrode) to the current detecting circuit 13 a (first currentdetecting circuit), and connects the linearization pattern sections 30 a(upper-right section: fourth electrode, lower-right section: thirdelectrode) to the current detecting circuit 13 b (second currentdetecting circuit).

In the meantime, in the period for detecting the position y (y directionthat is a second direction), the display device 500 connects thelinearization pattern sections 30 a (lower-left section, lower-rightsection) to the current detecting circuit 13 a, and connects thelinearization pattern sections 30 a (upper-left section, upper-rightsection) to the current detecting circuit 13 b.

The connection is switched by controlling the current detectingdirection changeover switch 521 by a current detection switching controlcircuit (not shown). In this case, a “detecting period switching controldevice” can be configured with the current detecting directionchangeover switch 521, the current detection switching control circuit(not shown), the current detecting circuit 13 a (first current detectingcircuit), and the current detecting circuit 13 b (second currentdetecting circuit).

This “detecting period switching control device” is capable of executinga switching control of the detecting periods for detecting the contactposition by dividing it to a first position detecting period fordetecting the position in the first direction on the conductiveimpedance surface and to a second position detecting period fordetecting the position in the second direction which crosses with thefirst direction.

Further, FIG. 12 shows the case where the linearization pattern sections30 a are extended from the vicinity of the four corners towards thecenters of the respective neighboring sides on the four sides of theouter periphery of the display device substrate 10, as in the case ofthe fourth exemplary embodiment. However, it is also possible to providethe plurality of divided linearization pattern sections 30 b on the foursides of the outer periphery of the display device substrate 10, as inthe case of the first exemplary embodiment.

Further, while FIG. 12 shows the case of providing the anisotropicconductor 34 which electrically connects the linearization patternsections 30 on the display device substrate 10 to the transparentconductive film (counter electrode) and seals the liquid crystal 2 atthe same time, it is also possible to form the anisotropic conductors 34separately for each function.

Next, the effects of the fifth exemplary embodiment (FIG. 12) will bedescribed by referring to a case where the position x (touched by afinger) in the x direction is detected.

When a finger touches the surface of the LCD, the potential of thetransparent conductive film (counter electrode) corresponding to thetouched part 26 drops. Through connecting the linearization patternsections 30 (lower left, upper left) provided in the vicinity of thefour corners of the display device substrate 10 to the same currentdetecting circuit 13 a, however, there is generated an effect of keepingthe uniform potential in the side connecting the linearization patternsections 30 a (lower left, upper left).

It is possible to keep the uniform potential in the side connecting thelinearization pattern sections 30 a (upper right, lower right) in thesame manner. As a result, there is a potential gradient generated in thex direction by having the area of the transparent conductive film(counter electrode) corresponding to the touched position 26 as theminimum. However, the potentials become uniform in the y direction, andequipotential lines in parallel to the y direction can be formed.

As described above, with this exemplary embodiment, the potentialdistribution becomes one-dimensional, so that the information regardingthe position y can be eliminated in the period for detecting the xposition. Therefore, it is possible to achieve an effect of improvingthe detection accuracy regarding the position x, while achieving thesame operational effects as those of the first exemplary embodiment.

Further, the same is true for the case of detecting the position ytouched by the finger.

Furthermore, the four current detecting circuits 13 required in thefirst exemplary embodiment (FIG. 1) can be reduced to two circuits.Therefore, the manufacturing cost of the current detecting circuits 13can be reduced to half in the case of FIG. 12 where the currentdetecting circuits 13 are reduced to two circuits.

Furthermore, the display device of the fifth exemplary embodimentdescribed above can also be formed as follows. That is, the firstpattern sections (30 a) of the linearization pattern sections includethe first to fourth electrodes (lower left, upper left, upper right,lower right) arranged in the four corners of the first substrate. Inthis case, the detecting period switching control device can include:the first current detecting circuit (13 a) which makes the potentials inthe second direction on one end side of the first direction uniform anddetects the electric currents in each of the first and second electrodesin the first position detecting period, and makes the potentials in thefirst direction on one end side of the second direction uniform anddetects the electric currents in each of the first and third electrodesin the second position detecting period; the second current detectingcircuit (13 b) which makes the potentials in the second direction on theother end side of the first direction uniform and detects the electriccurrents in each of the third and fourth electrodes in the firstposition detecting period, and makes the potentials in the firstdirection on the other end side of the second direction uniform anddetects the electric currents in each of the second and fourthelectrodes in the second position detecting period; and the currentdetection switching control circuit (not shown) which performs aswitching control regarding the connecting relations between each of thefirst to fourth electrodes and each of the first and second currentdetecting circuits.

Other structures, steps, functions, and operational effects thereof arethe same as those of the above-described exemplary embodiment. Further,it is also possible to put the processing contents of the manufacturingdevice used for the method for manufacturing through each of the stepsdescribed above, the structural elements of each part (circuit), andeach functions thereof into programs to have those programs executed bya computer.

Sixth Exemplary Embodiment

Next, a sixth exemplary embodiment of the invention will be described byreferring to FIG. 14. Hereinafter, the practically same structuralelements as those of the first exemplary embodiment are omitted, andonly different points will be described. FIG. 14 is a plan modelillustration showing an example of a schematic structure of a displaydevice according to the sixth exemplary embodiment of the invention.

This exemplary embodiment employs a structure where switching elementsare provided on the wirings for transmitting electric signals to theinside the display area form the outside the display area.

Specifically, as shown in FIG. 14, unlike the case of the fifthexemplary embodiment (FIG. 12), a display device 600 of this exemplaryembodiment is provided with a high-impedance switch part 16 (firsthigh-impedance switch), a high-impedance switch part 17 (secondhigh-impedance switch), and a high-impedance switch part 18 (thirdhigh-impedance switch) formed on the wiring part for transmittingelectric signals to a first circuit part within the display area from asecond circuit part of the outside the display area.

Note here that the second circuit part of the outside the display areamay be formed on the same substrate as that of the first circuit partwithin the display area or may be formed on an external substrate.

In a case where the second circuit part of the display area outside partmay be formed on the same substrate as that of the first circuit partwithin the display area, it is preferable to provide the high-impedanceswitch parts 16, 17, and 18 on the wiring part which connects thedisplay area outside part with the external substrate.

Specifically, the wiring part on which the high-impedance parts 16, 17,and 18 are provided are preferable to be at least one of the signallines 4, the scanning lines 6, the capacitance lines 8, and the powersupply lines (not shown).

Further, it is preferable to have a high-impedance switching controlcircuit for controlling the high-impedance switch parts, and preferablefor the high-impedance switching control circuit to control at least oneelectrodes for transmitting the electric signal from the display areaoutside part to the display area inside part to be in a high-impedancestate in a period where the current detecting circuit 13 detects thecurrent.

Note here that an “impedance control device” can be configured with thehigh-impedance switch parts 16, 17, 18 and the high-impedance switchingcontrol circuit. This “impedance control device” may be formed on thedisplay device substrate or may be formed on a separate control circuitsubstrate.

During the detecting period for detecting a contact position, this“impedance control device” can control the first circuit part within thedisplay area of the first substrate to be in electrically higherimpedance compared to that of the second circuit part that is outsidethe display area. Further, the “impedance control device” can controlthe first circuit part and the second circuit part to be in anon-conductive state. Furthermore, the “impedance control device” caninclude: a high-impedance switch part formed on the wiring part whichconnects the first circuit and the second circuit; and a high-impedancecontrol circuit which performs on/off controls of the high-impedanceswitch part.

Next, operations of the high-impedance switch parts will be described.

For making it possible to control the circuit within a pixel matrix partand the circuit in the outer peripheral part of the display area to beelectrically high impedance, in the outer-peripheral part of the displayarea, the high-impedance switch part 16 is provided to each signal pathof the scanning lines 6, the high-impedance switch part 17 is providedto each signal path of the signal lines 4, and the high-impedance switchpart 18 is provided to each signal path of the storage capacitance lines8.

Switching of the high-impedance switch parts 16, 17, and 18 iscontrolled by the high-impedance switching control circuit, not shown.This makes it possible to control the scanning line 6 and the signalline 4 for transmitting the electric signals from the outside thedisplay area to the inside thereof to be in a high-impedance state.

The vertical blanking period is utilized for the position detectingperiod. In the position detecting period, the high-impedance switch part16, the high-impedance switch part 17, and the high-impedance switchpart 18 are all set to off-state as in FIG. 14, and the signal line 4,the scanning line 6, and the storage capacitance line 8 are set to be inhigher impedance with respect to the wirings (connected to the scanningline driving circuit 14, the signal line driving circuit 15, and the COMterminal) on the outer side of the display area.

Further, in the position detecting period, the current directiondetecting switch 521 is in a conductive state with the AC voltage source22 side including the current detecting circuits 13. In the state shownin FIG. 14, same-phase AC voltages generated by the AC voltage source 22is applied to the linearization pattern sections 30 a which are providedin the vicinity of the four corners of the display device substrate 10.

The linearization pattern sections 30 a formed in the vicinity of thefour corners of the display device substrate 10 are electricallyconnected to the transparent conductive film via the anisotropicconductor 34. Thus, the AC voltages are applied to the vicinity of thefour corners of the transparent conductive film.

Further, FIG. 14 shows the case where the linearization pattern sections30 a are extended from the vicinity of the four corners towards thecenters of the respective neighboring sides on the four sides of theouter periphery of the display device substrate 10. However, it is alsopossible to provide a plurality of divided linearization patternsections 30 b on the four sides of the outer periphery of the displaydevice substrate 10.

FIG. 15 is a timing chart showing voltages of electrodes of the displaydevice according to the sixth exemplary embodiment. The voltage of thetransparent conductive film is shown as Vc in FIG. 15.

Referring to the timing chart of the voltages shown in FIG. 15, eachscanning line 6 is in a high-impedance state and capacitance thereof iscoupled with the transparent conductive film. Therefore, the voltage Vgof the scanning line 6 fluctuates with the same amplitude as the voltageamplitude of the transparent conductive film.

As described above, with the sixth exemplary embodiment, the circuitwithin the pixel matrix part is set to be in a higher impedance statecompared to the circuit on the outside in the position detecting period.Therefore, it is possible to achieve an effect of keeping a parasiticcapacitance extremely small from the viewpoint of the transparentconductive film 12 side when the AC voltage is applied to thetransparent conductive film, while achieving the same operationaleffects as those of the first exemplary embodiment. Specifically, whilethe parasitic capacitance with the related technique is 15 nF, forexample, the parasitic capacitance can be reduced to as small as 100 pFwith the use of the sixth exemplary embodiment.

As a result, with the use of the sixth exemplary embodiment, the S/Nratio of the signal outputted from the current detecting circuits 13 canbe multiplied by 150 times (6×10⁻², for example), whereas it is 4×10⁻⁴,for example, with the related technique.

Further, both the gate voltage and the source voltage of the transistorchange with the same amplitude as the voltage amplitude of thetransparent conductive film. Thus, relative differences of the gatevoltage and the source voltage can be made uniform, so that Vgs of thetransistor is not fluctuated. This results in achieving such a specialeffect that it is possible to minimize the influence of the drive in theposition detecting period imposed upon the image quality.

This exemplary embodiment uses the n-type TFTs for the high-impedanceswitch parts 16, 17, and 18 for making the inside and outside of thedisplay area electrically high impedance. However, the high-impedanceswitch parts may be of p-type TFTs or may be a transfer gate formed witha combination of n-type and p-type.

Other structures, steps, functions, and operational effects thereof arethe same as those of the above-described exemplary embodiment. Further,it is also possible to put the processing contents of the manufacturingdevice used for the method for manufacturing through each of the stepsdescribed above, the structural elements of each part (circuit), andeach functions thereof into programs to have those programs executed bya computer.

Seventh Exemplary Embodiment

Next, a seventh exemplary embodiment of the invention will be describedby referring to FIG. 16 and FIG. 17. Hereinafter, the practically samestructural elements as those of the first exemplary embodiment areomitted, and only different points will be described. FIG. 16 is a planmodel illustration showing an example of a schematic structure whichillustrates a relation between linearization pattern sections and ananisotropic conductor of a display device according to the seventhexemplary embodiment of the invention. FIG. 17 is a fragmentarysectional view showing a IV-IV′ part of FIG. 16.

While the first exemplary embodiment shows the structural example of theliquid crystal display device, the seventh exemplary embodiment shows astructural example of an electrophoretic display device which utilizesmicro-capsule type electrophoretic elements.

Specifically, as shown in FIG. 16 and FIG. 17, a display device 700according to this exemplary embodiment is an electrophoretic displaydevice (referred to as EPD hereinafter) which utilizes the micro-capsuletype electrophoretic elements, and it is a monochromatic EPD activematrix display. The display device 700 has a counter substrate 19, anEPD film 102, and a display device substrate 10.

The counter substrate 19 has a counter electrode 12 made of atransparent conductive film formed on the inner-surface side of atransparent plastic substrate 23 formed with polyethylene terephthalateor the like, for example. The counter substrate 19 may be formed byusing a glass substrate instead of the plastic substrate 23.

As shown in FIG. 17, the EPD film 102 is a film-type electrophoreticdisplay device, which is configured with micro capsules 113 and abinder. The micro capsules 113 are filled inside the EPD film 102, andthe size thereof is about 40 μm. A solvent 115 made with isopropylalcohol (IPA) or the like is inserted inside the micro capsules 113, inwhich white particles 116 (titanium oxide based white pigment) innano-level size and black particles 117 (carbon based black pigment) innano-level size are dispersed to float in the solvent 115. The whiteparticles 116 have minus (−) charged polarity, and the black particles117 have plus (+) charged polarity. The binder is formed with polymerfiled between the micro capsules 113 for coupling those to each other.

The display device substrate 10 has a structure in which TFTs are formedon the glass substrate 23. The TFT is an inverted staggered type inwhich gate G is arranged on the glass substrate 23 side with respect tosource A and drain D.

Regarding the TFT, the gate G is formed on the glass substrate 23, aninsulating film 72 to be a gate insulating film is formed on the gate G,a channel material 73 is formed on the insulating film 72, the source Sand the drain D are formed on both outer sides of the channel material73, an insulating film 74 is formed on the insulating film 72 includingthe channel material 73, the source S, and the drain D, a pixelelectrode 5 is formed on the insulating film 74, and the pixel electrode5 is via-connected to the source S.

In FIG. 16, the gate G of each TFT is electrically connected to thecorresponding scanning line (not shown), and the drain D of each TFT iselectrically connected to the corresponding signal line (not shown).

When a voltage is applied to the gate G, the + voltage applied to thedrain D is supplied to the pixel electrode 5 through the channelmaterial 73 and the source S. When the + voltage is supplied to thepixel electrode 5, the white particles 116 in the corresponding microcapsule 113 are drawn to the pixel electrode 5 side, and the blackparticles 117 in the micro capsule 113 are relatively drawn to thecounter electrode 12.

In the meantime, when the − voltage is supplied to the pixel electrode5, the black particles 117 in the corresponding micro capsule 113 aredrawn to the pixel electrode 5 side, and the white particles 116 in themicro capsule 113 are relatively drawn to the counter electrode 12. Inthis manner, with the display device shown in FIG. 16, white and blackimages can be displayed on the counter electrode 12 side by supplyingthe + voltage or the − voltage to the pixel electrode 5.

In the seventh exemplary embodiment, the linearization pattern sections30 formed on the display device substrate 10 are also covered by theanisotropic conductor 34, and the anisotropic conductor 34 is also incontact with the transparent conductive film 12. The display devicesubstrate 10 and the transparent conductive film 12 are made conductiveand the resistance in a specific area of the transparent conductive film12 is reduced through electrically connecting the linearization patternsections 30 on the display device substrate 10 and the transparentconductive film 12 via the anisotropic conductor 34.

Further, FIG. 16 shows the case where the linearization pattern sections30 a are extended from the vicinity of the four corners towards thecenters of the respective neighboring sides on the four sides of theouter periphery of the display device substrate 10. However, it is alsopossible to provide the plurality of divided linearization patternsections 30 b on the four sides of the outer periphery of the displaydevice substrate 10.

Further, a single-pole double-throw type switch is connected to theelectrodes of the display device substrate 10. The current detectingcircuit and the AC voltage source are connected in series to one ofconnections of the switch, and a COM terminal to which the counterelectrode driving circuit is connected is connected to the otherconnection (not shown).

As in the case of the sixth exemplary embodiment (FIG. 14), the seventhexemplary embodiment may be structured in such a manner that: a signalline driving circuit for driving the signal liens and a scanning linedriving circuit for driving the scanning lines are provided on the outerside of the display area; the switches are provided on the signal pathbetween the scanning line and the signal path between the signal lineand the signal driving circuit; and the wirings for transmitting theelectric signals from the outside the display area to the inside are setto a high-impedance state.

Further, as in the case of the first exemplary embodiment, regarding itsdrive, the display device according to the seventh exemplary embodimentalso has two periods such as a display drive period and a positiondetecting period. The display drive period is a period for writing avoltage for achieving pixel display. The position detecting period is aperiod where the current detecting circuit detects the electric currentin order to detect coordinates of a finger position and to detectwhether or not there is a pointing action. Those two periods are dividedin terms of time.

As described above, the EPD of the seventh exemplary embodiment iscapable of exhibiting a property which can keep a display for a longtime after writing a voltage for the display, while achieving the sameoperational effects as those of the above-described exemplaryembodiments. Thus, a larger proportion can be used for the positiondetecting period compared to the case of the LCD.

Further, it is possible to achieve a display device having a flexiblecharacteristic and a touch sensor function through thinning the displaydevice substrate 10 or transferring the pixel circuit to a flexiblesubstrate.

Other structures, steps, functions, and operational effects thereof arethe same as those of the above-described exemplary embodiment.

Other Various Modification Examples

While the device and the method according to the present invention havebeen described by referring to some of the specific exemplaryembodiments, various modifications can be applied to the exemplaryembodiments depicted in the contents of the present invention withoutdeparting from the technical spirit and the scope of the presentinvention.

For example, while each of the above exemplary embodiments has beendescribed by referring to the cases of the liquid crystal display deviceor the electrophoretic display device, those exemplary embodimentssurely can be applied to display devices of other types which utilizecharged particles, an electro chromic material, an electro luminescencematerial (EL material), a gas, a semiconductor, a semiconductor, and aphosphor, for example.

Further, the number, positions, shapes and the like of theabove-described structures are not limited to those described in theexemplary embodiments, but may be set to preferable number, positions,shapes, and the like for embodying the present invention. That is, whilethe exemplary embodiments have been described by referring to the caseof having 6×4 numbers of dummy patterns among the linearization patternsections, the present invention is not limited to such number.

Further, the linearization pattern sections are not limited to be formedin the geometrical shape as in the drawings. For example, thelinearization pattern sections can be formed in a more complicated andfine form to improve the detection accuracy.

The liquid crystal display devices according to each of theabove-described exemplary embodiments can be used as display units ofvarious kinds of electronic apparatuses. Examples of the electronicapparatuses may include various kinds of electric products such as:various kinds of information processors such as a television set of thebroadcast receiving device of the above-described exemplary embodiment,computers, and the like; remote controllers of various kinds ofapparatuses; home appliances, game machines, and portable music playersto which various kinds of information communicating functions areloaded; various kinds of recording devices; car navigation devices;pagers; electronic notebooks; pocket calculators; word processors; POSterminals; various kinds of mobile terminals; portable devices such asPDAs, portable telephones, wearable information terminals, PNDs, andPMPs; and display devices loaded on game machines such as pachinkomachines.

Further, the display device substrate used as the first substrate toconfigure the display device may be considered as a target of thepresent invention.

In that case, the display device substrate according to the presentinvention can be used as the first substrate for configuring the displaydevice which: displays an image by having display elements capable ofperforming electro-optic responses formed between the conductible firstand second substrates; and are capable of detecting a contact positiontouched by a contact body by having a conductive impedance surfaceformed on the second substrate side.

The display device substrate can include: a pixel matrix part in which aplurality of pixels are formed in matrix; and linearization patternsections including a plurality of electrodes formed in a peripheral areaof the pixel matrix part, which are capable of performing linearizationof electric fields of the conductive impedance surface and capable ofdetecting electric currents on the conductive impedance surface.

Further, the control circuit such as an external substrate forconfiguring the display device can be considered as a target of thepresent invention.

In that case, the control circuit of the display device of the presentinvention can be electrically connected to the display device whichdisplays images by having the display device capable of performingelectro-optic response formed between the conductible first and secondsubstrates so as to perform a control to detect a contact positiontouched by a contact body by having the conductive impedance surface onthe second substrate side.

The control circuit of the display device can include: a detectingdevice (current detecting circuit, etc.) for detecting the flowingelectric currents at a plurality of points on the conductive impedancesurface; and a detecting period switching control device which performsswitching controls by dividing the detecting period for detecting thecontact position to a first position detecting period for detecting theposition in the first direction on the conductive impedance surface andto a second position detecting period for detecting the position in thesecond direction which crosses with the first direction.

Further, the control circuit of the display device can further includean impedance control device which can control the first circuit withinthe display area of the first substrate to be in electrically higherimpedance compared to that of the second circuit part that is outsidethe display area, during the detecting period for detecting the contactposition.

Furthermore, the manufacturing method of the display device substratefor configuring the display device (display device substratemanufacturing method) can also be considered as a target of the presentinvention.

In that case, the display device substrate manufacturing method canmanufacture the display device substrate that can be used as the firstsubstrate for configuring the display device which: displays an image byhaving display elements capable of performing electro-optic responsesformed between the conductible first and second substrates; and arecapable of detecting a contact position touched by a contact body byhaving a conductive impedance surface formed on the second substrateside.

The display device substrate manufacturing method can include: a firststep which forms, on the first substrate, linearization pattern sectionsincluding a plurality of electrodes formed in a peripheral area of thepixel matrix part, which are capable of performing linearization ofelectric fields of the conductive impedance surface and capable ofdetecting electric currents on the conductive impedance surface.

The first step can be performed simultaneously with a step for formingthe pixel electrode on the first substrate or a step for forming thewirings on the first substrate.

Further, a part of each block shown in the drawings or the controlcircuits that are not shown (the circuit for controlling the switches,the high-impedance switching control circuit, the current detectionswitching control circuits, etc.), the circuit configuring the positioncalculating part for calculating the position, etc. may be softwaremodule structures which are functionalized by various kinds of programsthrough executing such programs stored in a proper memory by a computer.

That is, even though the physical structure is a single or a pluralityof CPU(s) (or a single or a plurality of CPU(s) and a single or aplurality of memory(s)) or the like, the software structure by each part(circuits, devices) can be considered a form in which a plurality offunctions implemented by the CPU with controls of the programs areexpressed as feature elements of each of the plurality of parts(devices).

When the dynamic state (each procedure configuring the program is beingexecuted) where the CPU is executed by the program is expressedfunctionally, it can be expressed that each part (device) is builtwithin the CPU.

In a static state where the program is not being executed, the entireprogram (or each program part included in the structure of each device)for achieving the structure of each device is stored in a storage areaof the memory or the like.

Explanations of each part (device) provided above can be taken as theexplanations of the computer that is functionalized by the programtogether with the functions of the program, or can be taken as a devicethat is configured with a plurality of electronic circuit blocksfunctionalized permanently by proper hardware. Therefore, thosefunctional blocks can be achieved in various forms, e.g., only withhardware, only with software, or a combination of both, and it is not tobe limited to any one of those forms.

Furthermore, the scope of the present invention is not limited to theexamples shown in the drawings.

Moreover, each of the exemplary embodiments includes various stages, andvarious kinds of inventions can be derived therefrom by properlycombining a plurality of feature elements disclosed therein. That is,the present invention includes combinations of each of theabove-described exemplary embodiments or combinations of any of theexemplary embodiments and any of the modifications examples thereof. Inthat case, even though it is not specifically mentioned in the exemplaryembodiments, the operational effects that are obvious from eachstructure disclosed in each of the exemplary embodiments and themodification examples thereof can naturally be included as theoperational effects of the exemplary embodiments. Inversely, thestructures that can provide all the operational effects depicted in theexemplary embodiments are not necessarily the essential feature elementsof the substantial feature parts of the present invention. Furthermore,the present invention can include structures of other exemplaryembodiments in which some of the feature elements are omitted from theentire feature elements of the above-described exemplary embodiments, aswell as the technical scope of the structures based thereupon.

The descriptions regarding each of the exemplary embodiments includingthe modification examples thereof are presented merely as examples ofvarious embodiments of the present invention (i.e., examples ofconcretive cases for embodying the present invention) for implementingeasy understanding of the present invention. It is to be understood thatthose exemplary embodiments and the modification examples thereof areillustrative examples, and not intended to set any limitationstherewith. The present invention can be modified and/or changed asappropriate. Further, the present invention can be embodied in variousforms based upon the technical spirit or the main features thereof, andthe technical scope of the present invention is not to be limited by theexemplary embodiments and the modification examples.

Therefore, each element disclosed above is to include all the possibledesign changes and the equivalents that fall within the technical scopeof the present invention.

The present invention can be applied to display devices in general. Morespecifically, as away of application examples, the present invention canbe applied to display devices which are used for game machines, portableinformation terminals, ticket-vending machines, automated tellermachines (ATM), car navigation systems, TV game machines provided atpassengers seats of airplanes or buses, factory automation (FA)equipment, printers, facsimile machines, etc.

What is claimed is:
 1. A display device which displays an image, thedisplay device configured to include an electro-optic material between athin film transistor substrate on which a thin film transistor is formedand a counter substrate, wherein linearization pattern sections and apixel area in which a plurality of pixel electrodes for supplyingelectric signals to the electro-optic material are formed on the thinfilm transistor substrate, the counter substrate includes a counterelectrode, an anisotropic conductor is arranged at least at a part of aperipheral area of the pixel area between the thin film transistorsubstrate and the counter substrate, and the linearization patternsections, the anisotropic conductor, and the counter electrode aresequentially arranged from bottom to top in this order, and theanisotropic conductor electrically connects the linearization patternsections with the counter electrode.
 2. The display device as claimed inclaim 1, wherein the conductive member is interposed between the thinfilm semiconductor substrate and the counter substrate to also work as asealing device for sealing the electro-optic material.
 3. The displaydevice as claimed in claim 1, wherein the anisotropic conductor isformed by being divided into a plurality of pieces.
 4. The displaydevice as claimed in claim 1, wherein: a first linearization patternsection is formed to extend from a corner of the thin film semiconductorsubstrate towards side areas in a range from the corner to vicinity ofcenters of the sides.
 5. The display device as claimed in claim 4,wherein: a second linearization pattern section has a plurality oflayers of conductive films which configure pixels or a peripheralcircuit formed on the thin film semiconductor substrate, and aninterlayer insulating film between the plurality of conductive films;and no contact hole is formed in the interlayer insulating film.
 6. Thedisplay device as claimed in claim 1, comprising a detecting periodswitching control device which performs switching controls whendetecting positions in each direction, by dividing a detecting periodfor detecting a contact position to a first position detecting periodfor detecting a position in a first direction on a conductive impedancesurface on the counter substrate and to a second position detectingperiod for detecting a position in a second direction which crosses withthe first direction.
 7. The display device as claimed in claim 1,further comprising an impedance control device which can control a firstcircuit part within a display area of the thin film semiconductorsubstrate to be in electrically higher impedance compared to that of asecond circuit part that is outside the display area and control thefirst circuit part and the second circuit part to be in a non-conductivestate, during a detecting period for detecting a contact position. 8.The display device as claimed in claim 7, wherein the impedance controldevice includes: a switch part formed on wirings which connect the firstcircuit part with the second circuit part; and a control circuit whichperforms on/off controls of the switch part.
 9. The display device ofclaim 1, wherein the display device is further configured to includedisplay means for displaying an image by a plurality of display elementsprovided between the thin film transistor substrate and a secondsubstrate, comprising: thin film transistor substrate in which thelinearization pattern sections, a control part of the display elements,and wirings are formed; the second substrate which opposes against thelinearization pattern sections, has a conductive impedance surfaceformed thereon, and measures, at a plurality of points, electric currentvalues flown at a contact point touched by a contact body to detect acontact position; and conductive means for electrically connecting thelinearization pattern sections and the conductive impedance surface. 10.The display device as claimed in claim 1, wherein a pattern of theanisotropic conductor covers an entirety of the linearization patternsections.
 11. The display device as claimed in claim 1, wherein apattern of the anisotropic conductor is formed in a frame shape.
 12. Thedisplay device as claimed in claim 1, wherein the linearization patternsections are configured with stacked layers of a plurality of conductivelayers on the thin film transistor substrate.
 13. The display device asclaimed in claim 1, wherein the linearization pattern sections have aconductive layer forming a signal line on the thin film transistorsubstrate or a conductive layer forming the plurality of pixelelectrodes.
 14. An electronic apparatus, comprising the display deviceclaimed in any one of claims 1 to 13 loaded thereon.
 15. The displaydevice as claimed in claim 1, further comprising a current detectingcircuit configured to detect a current flown in the counter electrodevia the anisotropic conductor and the linearization pattern sections.16. The display device as claimed in claim 15, further comprising an ACvoltage source configured to supply AC voltages to the counter electrodevia the anisotropic conductor and the linearization pattern sections.17. A manufacturing method of a display device that displays an image,the display device configured to include an electro-optic materialbetween a thin film transistor substrate on which a thin film transistoris formed and a counter substrate, the method comprising: a first stepof forming a pixel area in which a plurality of pixel electrodes thatsupply electric signals to the electro-optic material are arranged, andsimultaneously forming linearization pattern sections on the thin filmtransistor substrate; a second step of forming an counter electrode onthe counter substrate; and a third step of arranging an anisotropicconductor at least at a part of a peripheral area of the pixel areabetween the thin film transistor substrate and the counter substrate,wherein the linearization pattern sections, the anisotropic conductor,and the counter electrode are sequentially arranged from bottom to topin this order.
 18. The manufacturing method as claimed in claim 17,wherein the first step includes photolithography or etching.